No, These Biohackers Can't Give Themselves Infrared Vision

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No, These Biohackers Can't Give Themselves Infrared Vision

Humans aren't designed to see the world in infrared. But California-based biohacking collective Science for the Masses thinks they can change that—all through a simple (though not that simple) change in diet.

It sounds like the kind of crazy idea that only a techie with too much time and money would come up with, but the concept isn't actually that new. During World War II, the U.S. Navy fed volunteer sailors a diet that substituted vitamin A for vitamin A2, in an effort to increase night vision. Though the results were apparently promising, the U.S. scrapped the study when researchers successfully developed an electronic snooperscope to see infrared. Now, this group of self-described home surgery enthusiasts is trying out the experiment again, in a project they're calling Human NIR Visual Perception Project1.

How is eating a different set of vitamins supposed to change the way you see? It has to do with the composition of light-sensitive pigments in our retinas, which only react to certain wavelengths of light—from violet, at about 390 nm, to red, around 720 nm. Those pigments are composed of photoreceptor molecules called opsins, along with a derivative of vitamin A called retinol. Humans have two pigments: photopsin in the color-perceiving cones, and rhodopsin in the light-and-dark rods. But fish, along with some amphibians and crustaceans that live in dark, murky waters, have another pigment called porphyropsin that's sensitive to wavelengths beyond 720 nm, closer to the infrared rangle. And it's built in part out a derivative of vitamin A2.

The theory is that a human who consumes only vitamin A2 will be forced to generate porphyropsin—and thus have the ability to see in infrared. But can these biohackers really create IR vision through a brute force metabolic hack? The short answer is no. The long answer is still no, but, it's not completely out of the question—depending on who you ask.

Although the maximum perceived wavelength for some animals is higher than in humans, it's not that much higher. In comparison to rhodopsin, porphyropsin’s sensitivity is shifted slightly upward, from blue to blue-green, explains Michael Marmor, a professor of ophthalmology at Stanford University’s School of Medicine. "It's still very insensitive to infrared," he says.

Those numbers suggest that it's possible for humans to shift their visual perceptive limits through their diets—but the shift in sensitivity should be relatively small. “The shift the participants should expect to see, should they switch completely from vitamin A[1] to A2, is about 20 nanometers," says Vladimir Kefalov, a professor of ophthalmology at Washington University's School of Medicine. "That’s not really extending the maximum limit very far into infrared."

That means the electroretinography (ERG) data the biohacking group published several months ago, which claimed to show that participants had actually pushed their perception up to 950 nm, is probably bunk. Both Marmor and Jacque Duncan, an ophthalmologist at UCSF Medical Center, found the ERG results riddled with noise that made it hard to interpret. When asked if the biohackers' goal was achievable, Marmor simply answered, "absolutely not."

Even more, avoiding vitamin A can create some serious health problems. Back when the Navy tested this out, it seems that one of the problems was a severe vitamin A deficiency, which can lead to eye disorders and immune weaknesses. And it's not just lack of vitamin A that causes problems: One of its metabolites, retinoic acid—which can't be made from vitamin A2—is critical for many processes in the liver, stomach, and the eye itself. The Science for the Masses crew is attempting to solve that problem by supplementing their diet with a special retinoic acid-enriched blend of Soylent (of course they're using Soylent), but Hui Sun, a professor of physiology at UCLA's Jules Stein Eye Institute, still raises concerns. "Retinoic acid's high reactivity makes it extremely toxic when directly administered to the human body," Sun wrote in an email. "Retinoic acid-based drugs are known to cause multi organ systemic toxicity." Whoops!

Jeffrey Tibbetts, from Science For the Masses, defends his group's work. "There is no doubt our biggest restriction was our ERG data," he says. "ERGs are just notoriously difficult to work with." And he says the group was careful to keep retinoic acid doses low enough to avoid any toxicity. When it comes to criticisms of the group's overall hypothesis, he points to the group's background research amassed from several decades of data—some as far back as the 1930s and 40s—listed on the project's webpage. Overall, Tibbetts emphasizes that the group is just looking to satisfy their innate curiosity. "It's something to look into, and that's why we’re doing it in the first place."

It's a fair point—after all, if they figured it out, wouldn't you want to have supersonic vision too? And there's interesting science that points to other ways to tweak your vision, even if they don't pull this method off. A recent study published by Kefalov and his colleagues found that sometimes, a single pigment molecule will absorb two photons simultaneously, especially if a photon has a wavelength over 900 nm, in the infrared spectrum. The energy of a photon is proportional to its wavelength, meaning two photons at 1000 nm have the same energy as one photon at 500 nm (green light). You can't perceive a wavelength of 1000 nm, but if two 1000 nm photons hit a pigment molecule at the same time, they produce an effect that's "indistinguishable to the perception of green light," says Kefalov. Sure, it's not exactly the night vision solution you've been looking for; you're not seeing in infrared, just the effects of that infrared light's energy. Maybe another weird quirk of visual perception for Science For the Masses to look into.